The IEEE 802.11ax specifications define high efficiency (HE) transmissions from an access point (AP) to a single station (STA) using single user (SU) multiple-input multiple-output (MIMO) (SU-MIMO) and to multiple STAs using multi-user MIMO (MU-MIMO) and orthogonal frequency division multiple access (OFDMA). The data packet transmitted is called a HE physical layer convergence procedure (PLCP) protocol data unit (PPDU). A special PPDU called the MU PPDU includes the data streams meant for multiple STAs transmitted using MU-MIMO and/or OFDMA. When SU-MIMO is used, the packet is called SU PPDU. The header to both SU and MU PPDUs includes information necessary to decode the PPDU. Since the same header has to indicate different types of payload to the receiver's physical layer, HE-signaling-A (HE-SIG-A) field in the header have multiple interpretations depending on certain flags that are transmitted along with the signaling fields. The MU PPDU has an additional HE-SIG-B field that communicates decoding information for the data addressed to the STAs.